These can both leave bristles and fibre in the wet paint. It’s worth spending a little more and buying better quality. In addition, remove loose bristles for the brush and rub the roller before use to remove any loose fibre. Such material when left in the cured pool paints will create a hard lump which is abrasive to skin.
Budget on about $10 – 15+ for a good brush and $15 – 25 for a good roller sleeve.
The nap of the roller should be about 10 – 12 mm for Smooth Surfaces (Fibreglass) and longer for rougher surfaces. For Marblesheen 12 – 15 mm and for Pebblecrete 20 -25 mm. Lambs wool may also be used. Full details in the Application Notes.